Simon Rattle’s all-American evening with the London Symphony Orchestra was dominated by George Gershwin. Boisterous, brassy performances of two of Gershwin’s overtures, to Let ’Em Eat Cake and Strike Up the Band, in orchestral arrangements by Don Rose, topped and tailed the concert, while Kirill Gerstein was the typically deft soloist in the sometimes rambling Piano Concerto in F, adding an even more agile account of Earl Wild’s paraphrase of I Got Rhythm as his encore. But there were also two much less familiar pieces in the programme, one of them entirely new and the other very rarely performed (on this side of the Atlantic at least).

The premiere came from John Adams. Commissioned by the LSO and dedicated to Rattle, Frenzy is an 18-minute orchestral workout, Adams’s most substantial since City Noir in 2009. Steadily building in intensity in the manner of pieces such as Short Ride in a Fast Machine, it takes a theme from his most recent opera, Antony and Cleopatra, as its starting point, and the source of all the musical material that follows. Adams describes it as a “kind of ‘short symphony’, encompassing in a relatively brief duration a variegated yet unified symphonic structure”, yet on first hearing it seemed more showpiece than symphony, and one that Rattle and his orchestra presented quite brilliantly.

The programme’s other novelty, though, was indisputably a “short symphony”, and a real discovery – the third of Roy Harris’s 18 symphonies. It is a strikingly original piece from 1939 whose continuous five-section structure seems to be modelled on that of Sibelius’s Seventh Symphony (while adding a touch of the unclouded modal string writing that opens his Sixth Symphony, too), yet is unmistakably American in its rangy themes with their tinge of yearning new deal optimism. It’s a taut, muscular and fiercely concentrated work; though its duration may be exactly that of Adams’s Frenzy, as Rattle’s superb performance showed, Harris’s Third packs in so much more.

• Repeated at Bristol Beacon on 4 March